We use model theory to rigorously evaluate Q-Theory as proposed in Shih and Inkelas 2019 as an alternative to Autosegmental Phonology. We find that Q-Theory is remarkably similar to Autosegmental Phonology, contra some of Shih and Inkelas’s claims. In particular, Q-Theory does not eschew the association relation, in Q-Theory the tone-bearing unit is the vowel, and Q-Theory and Autosegmental Phonology are equivalent in terms of the constraints they can express. However, this formal analysis clarifies the truly novel contribution of Q-Theory, which is the empirical claim that all segments are tripartite.